I've seen a lot of discussion about this over on the Haynes forum (I would post there but it's not well used). The synopsis seems to be
that:
The book says 13" open and 9" closed (with a 1" extension)
Using an extension is not ideal nor does it allow choice of lots of suppliers (13" plus an extension apparently being an attempt to limit to one
supplier...).
There's argument about best closed length - between 9" and 9.5"

Someone on the Haynes forum told me that, to save using the extension, 14" open and 9" closed was a 'standard' available shock
size. And Andy Bates at AB has told me an extension is best avoided.

Now i'm lining up to actually buy a set Protech have told me that their Haynes suspension set is: open length is 14” and the close length is
approx 10.75”

2.25" travel seems too little for me, what is the wheel travel with that?
The more travel, the softer your suspension may be and more comfortable.
I am aiming for 4" travel, one third of that is used @ Ride Height.
Not a Haynes though.
AA

Photo Archive
Building: Haynes roadster on the Road since november 2014

posted on 29/10/18 at 02:20 PM

Hi John,

I'm surprised Protech closed length of their shocks for Haynes is 10.75''... I'm pretty sure they used to exist in
14'' open - 9.5'' closed.

If they don't, IMHO, you should stick to the 9'' or 9.5'' closed, not more.

A lot of us went for Gaz shocks, mostly because of the price (they are cheap, especially if you buy them from Rally Design). So far, I can't
complain about the quality, I'm happy with them, but again, I'm just using my Roadster on the road, not racing it on a track. And they do
exist in 14'' open - 9.5'' closed.

I'm pretty sure you already got the info from the Haynes Forum, but just in case, here are the details of the Gaz Shocks I bought from Rally
Design (for my Sierra based Haynes Raodster)

quote:Originally posted by ianhurley20
I went the same way as Sylvain from Rally Design Gaz make shocks
Mine were 14" open 9" closed but were ones that take 1.9" springs

I went for 9" springs 1,9" dia with 350lbs front and initially 250 lbs rear.

My 250lbs springs are currently for sale if they would help (my car was written off recently and had 300l ssprings on at the time)

Thanks for the offer (and info to add to what Sylvain has said) - i think i'll get a package from Protech though which will include everything.
That is if I can get the lengths I think i need from them!

Having just had a phone call with Protech - Sylvain, Ian, - are you using bump stops within your shock absorber setup and is the 14-9.5 range with a
bump stop in place or not? And how much travel do you loose with the bump stop?

The very helpful man I spoke to told me that they could use a shorter shock body and a shorter threaded end to the rod - to give another 10mm maybe -
but by my calculation this would only bring things from 10.75" closed to about 10.35" closed. I think the Protech measurement includes
having a 1" bump stop, disregard that and it mean things are coming a bit closer to the 9.0/9.5 closed figure...

I am afraid I can no longer check as my car was recently written off. Yes there was a bump stop and my understanding was that I had the full travel
with it in place but would have to check with Rallydesign for a definitive answer. I will say that they worked well and although I did bottom the car
out once with myself (15 stone) and a friend who is 6' 3" tall and I would guess a stone heavier and also with my 8.5 gallon fuel tank
nearly full on a country road I never used the full suspension travel of the shock absorber. It was the bottom of the car that grounded. The 250lb
springs were perfect for single occupant use but for two up its why I changed them to 300lb rear springs.

quote:Originally posted by ianhurley20
I am afraid I can no longer check as my car was recently written off. Yes there was a bump stop and my understanding was that I had the full travel
with it in place but would have to check with Rallydesign for a definitive answer. I will say that they worked well and although I did bottom the car
out once with myself (15 stone) and a friend who is 6' 3" tall and I would guess a stone heavier and also with my 8.5 gallon fuel tank
nearly full on a country road I never used the full suspension travel of the shock absorber. It was the bottom of the car that grounded. The 250lb
springs were perfect for single occupant use but for two up its why I changed them to 300lb rear springs.

Thanks Ian, apologies - i didn't mean to be insensitive given what's happened to your car!